For hosting common files it's ok. Also it is on Android too do, great to transfer files between your Windows and your phone. But if you want better security you have to subscribe a monthly offer.
SpiderOak - SpiderOak makes it possible for you to privately store, sync, share & access your data from everywhere.
Dropbox - Online Sync and File Sharing
CrashPlan - CrashPlan for Small Business backup software offers the best way to back up and store business & enterprise data securely - offsite, onsite & online in the Cloud.
Google Drive - Access and sync your files anywhere
Duplicati - Free backup software to store backups online with strong encryption. Works with FTP, SSH, WebDAV, OneDrive, Amazon S3, Google Drive and many others.
Mega - Secure File Storage and collaboration